When someone uploads a file during checkout (part of a form), where does the file go?

I added a form to the purchase flow of a digital product. Basically people can purchase ad placement in a catalog. We've given people the option to upload the file directly, but I have no idea where that file is going or how to see it. I also can't see where to change my settings for forms within checkout. I do see how that works in a regular form outside of checkout. Anyone have an answer?

For the example above, the only selection available is to purchase is the Breeder Directory for $15

Screengrabs show:

• Item for purchase
• Form within checkout flow
• What the order looks like when someone uploads a file (it looks like it's just referencing a file on her computer)